Bed spring



Dec. 1, 1959 [NTNER 2,914,778

I I BED SPRING Filed NOV; 23, 1956 zwm ATTORNEY.

,,United States P e BED SPRING Mathew Intner, New York, NY. Application November 23, 1956, Serial No. 623,864 1 Claim. (Cl. -231) The present invention relates generally to bed springs, and more particularly is directed to an improved bed spring especially suitable for use under a foam rubber mattress.

Heretofore, it has been the usual practice, in the bedding industry, to employ a box spring of conventional construction as'the support for a foam rubber mattress. However, sucha conventional box spring, which was originally designed for use with an inner spring mattress, does not provide adequate support for the recumbent human vforin when a foam rubber mattress is substituted for an inner spring mattress. The inadequate support of a conventional box spring combined with a foam rubber mattress is apparent, even when the latter is of the type identified as extra firm or very firm, and such special foam rubber mattresses are relatively expensive. Although various so-called no-sag and flat or link spring constructions have been proposed and used in connection with foam rubber mattresses, such springs do not. effect any substantial improvement in the character of the support afforded to the recumbent human form and, additionally, lowering the level of themattress by reason of the fact that most beds are intended to receive the relatively large thickness of a box spring rather than the relatively thin no sag or flat spring.

Accordingly, it is an object of the present invention to provide a bed spring, particularly, is particularly intended for'use in connection with a foam rubber mattress 'to provide a hitherto unattainable degree of support and comfort with such a mattress.

Another object is to provide a bed spring of the de scribed character which is constructed with a view to providing balanced support for the recumbent human form.

7 Another object is to provide a bed spring of the described character capable of providing a degreev of support and comfort with a foam rubber mattress of standard hardness or firmness that has heretofore been unatspringswhich it is intended to replace In accordance with an aspect of this invention, a box spring is provided with a wooden frame having rectangular upper and lower portions which are suitably spaced apart, a grid of pivotally interconnected, longitudinally and laterally extending'elongated elements supported within the upper portion of the frame by helical tension springs'connecting the ends ofthe grid to the adjacent endsof the upper frame portion and by secure attachment of the opposite sides of the grid to the adjacent.

sides of the upper frame portion, and an assembly of Further, in a box-spring embodying this invention, the ends of the wooden box frame are strengthened by laterally extending metal straps secured thereto and performing the additional function of serving to attach the previously mentioned helical tension springs to the ends of the upper frame portion..

A box-spring embodying this invention is also preferably characterized by the provision of angle braces which extend between the sides of the upper frame portion to resist relative lateral movement of such sides and which carry the coil springs supportingthe central portion of the grid, the braces and coil springs constituting a subassembly which can be conveniently produced independently of the other parts of the spring and then easily assembled with such other parts.

The above, and other objects, features and advantages of the invention, will be apparent in the following detailed description of an illustrative embodiment thereof which is to be read in connection with the accompanying drawing forming a part hereof, and wherein:

Fig. 1 is a top plan view of a bed spring embodying the present invention;

Fig. 2 is a fragmentary, enlarged sectional view taken along the line 22 of Fig. 1; I

Fig. 3 is an enlarged, detail view of a portion of the bed spring of Fig. 1;

Fig. 4 is a fragmentary, enlarged sectional view taken along the line 4-4 of Fig. 1; and

Fig. 5 is a side elevational view of a subassembly of braces and coil springs included in the bed spring of Fig. 1, but with the braces being broken away and shown in section.

have the disadvantage-of undesirably a box spring, which coil springs supporting the grid from beneath the latter at the central portion of the spring.

Referring to the drawing in detail, and initially to Fig. 1 thereof, it will be seen that a bed spring embodying the present invention, and there generally identified by the reference numeral 10, includes a wooden box frame 11 having upper and lower rectangular portions 12a and 12b (Fig. 2) each made up of side frame members 13 and end frame members 14 suitably joined together at the corners and preferably having corner braces 15. The upper and lower portions 12a-and 12b of the frame are held in parallel, spaced apart relation by interposed spacing members 16 (Fig. 2) which are disposed at suitable locations to provide the ,necessary rigidity, for example, at the corners and at locations midway along the side members 13 and the end members 14.

The bed spring 16 further includes a flexible grid which is generally identified by the reference numeral 17 and is made up of pivotally interconnected longitudinal members 18 and lateral members 19 arranged in rows parallel to the side frame members 13 and end frame members 14, respectively. As seen in Fig. 3, each of the longitudinal members 18 is preferably formed of a length of suitably rigid or hard wire which is bent upon itself, at its midpoint, to forman eye 10 which .is closed by twisting together the two parts of the bent length of wire, as at 21. The two parts of the bent length of wire extend parallel to each other from the twist 21 and, at their free ends, are bent to form a hook 22 (Fig.2) in a plane perpendicular to the plane of the related eye 20. Each of the lateral members 19 is preferably also formed from a length of suitably hard or grid wire having its opposite ends bent to form hooks 23 and 24 (Fig; 4) lying in the same plane.

In assembling the flexible grid 17 from the above described longitudinal member 18 and lateral members 19, rows of pivotally connected longitudinal members 18 are formed by engaging the hook 22 of each longitudinal member in the eye 20 of the next adjacent orsuccessive longitudinal member, while the lateral members 19 span the spaces between the adjacent rows 'of longitudinal members and the hooks 23 and 24 of each lateral memthe opposite ends of the wood frame 11 and to further resist failureof the joints at the corners of the frame. The'straps'ZS are also provided with holes 27 which are aligned with the several rows of longitudinal members '18 in the grid 17, and the opposite ends of the grid 17 are supported from the upper frame portion 12a by helical tension springs 28 which have hooks at their strap 25 and in the hooks 22 of'the related end members 18, respectively (Figs. 1 and 2). Thus, the straps 25,

in addition to strengthening the ends of frame 11, provide a convenient connection between the helical tension springs 28 and the adjacent ends of the frame.

The support for the grid 17 within upper frame portion 12a further includes lateral members 29 (Fig. 3) which are formed of lengths of suitably rigid wire having the opposite ends bent to define hooks lying in planes perpendicular to each other, such lateral members 29 being provided along the opposite side edges of the grid 17 at alternate rows of the lateral members 19 with a hook at one end of each member 29 engaging in the eye 20 of a related member 18 at the adjacent side edge of the grid and with the other hook of the member 29 extending over the adjacent sidefrarne member 13 of upper frame portion 12a and being conveniently secured" thereto by a staple 30 (Fig. 3) driven into the wooden side frame member. It is to be understood that the grid 17 is laterally tensioned during the driving of the staples 30 so that the members 29 securing the sides of the grid 17 to the adjacent side frame members of the upper frame portion will hold the grid in a laterally taut condition, while the helical springs 28 are also under tension to hold the grid 17 in a taut condition in the longitudinal direction.

Since the weight of a human form recumbent on a mattress of foam rubber on the bed spring 10 is greatest at the central portion of the latter, the bed spring embodying the present invention is further provided with an assembly, generally identified by the reference numeral 31 (Figs. 4" and for affording increased resistance to yielding of the grid 17 at the central portion of the latter. The assembly 3ll' inclndes laterally extending rows of compression coil springs 32, preferably in the form of conical helixes and arranged with the turns of largest diameter at the top and acting against the underside of grid 17. The upper turn of each coil spring 32 is secured tothe grid 17, for example, by circlets or clips 33 (Fig. 4) which embrace the upper turn of thecoil spring and adjacent longitudinal members 18 of the grid 17.

The lower ends of the coil springs 32 in each laterally extending row of the latter are supported by a related laterally extending angle member 34 of steel or iron having openings 35 therein to receive hooked lower ends of the coil springs32. As seen in Fig. 4, each of the opposite end portions of the angle member 34 is upwardly bent or'offset, as at 36, and has a fiat terminal part 37 that overlies and rests upon the upper surface of the adjacent side frame member 13 of upper frame portion 12a. Each terminal part 37 has a hole therein receiving a screw 38 thatis driven into the related side frame member 13 for securing the related angle members to the frame 11. Thus, the several rows of compression coil springs 32 are interposed between the grid 17 and the rigid angle members 34 to lend additional stiffness to the support of a mattressplaced on the bed spring at'the central portion thereof. The angle members 34, in addition to" supporting the rows of compression coil opposite ends engaging in the holes 27 of the adjacent springs 32, serve as lateral braces for the upper frame portion 12a and prevent deflection of the side frame members 13 toward each other under the influence of the load applied to the latter by the direct connection of the side edges of grid 17 to the adjacent side frame members.

In order to permit all of the compression coil springs 32 and the angle members 34 to be produced as a subassembly that can be installed, as a unit, within the frame 11, a plurality of tie wires 39 (Fig. 5), only one of which appears in the drawing, are extended longitudinally between the several laterally extending rows" of coil springs 32 which are hooked, at their lower ends, to the angle members 34. Each tie wire 39 has ofiset portions 40 corresponding to the several lateral rows of coil springs 32 and fitting within lower turns of the related coil springs so that the latter are threadably engaged with the offset portions 40. Thus, the tie wires 39 hold the rows of compression coil springs 32 and the related angle members 34 in parallel spaced apart relation. In assembling the various parts of the sub-assembly 31, the compression coil springs 32 are first threaded onto the related tie wires 39, and then the lower hooked ends of the coil springs are engaged in the openings 35 of the angle members 34 to thereafter prevent turning of the coil springs 32 so that the latter cannot be threadably disengaged from the tie wires 39.

The bed spring 10 embodying this invention, when combined with a foam rubber mattress of only ordinary hardness, provides a degree of support and comfort for a human form recumbent on the mattress that is unattainable with conventional box springs supporting even relatively expensive foam rubber mattresses of extra hardness. Such improved support and comfort results from the fact that the spring 10 provides only a generally slightly, overall yielding base for a foam rubber mattress, while the flexibly resilient foam rubber mattress is itself relied upon to provide the localized yielding for conformation to the contours of the human form recumbent thereon. Further, the assembly 31 of the bed spring 10 provides additional support at the center of the latter, where the greatest concentration of weight is normally disposed, thereby to prevent sagging of the spring and mattress under such concentrated weight.

It will also be apparent that'the bed spring 10, in employing the wood box frame 11, has a vertical dimension which is substantially the same as that of a conventional box spring, so that the spring embodying this invention can be conveniently substituted for a conventional box spring without altering the level of thetop surface of the supported mattress. Further, the combination of the wood box frame with the grid 17 of nonextensible longitudinal and lateral members 18 and 19, pivotally connected to each other and supported within the upper portion of the frame, and the use of metal cross members 25 and 34 to perform both supporting and bracing functions makes it possible to economically produce a bed spring having the above described ad- 'vantageouscharacteristics.

Although a particular embodiment of the invention has been described in detail herein with reference to the accompanying drawing, it is to be understood that the invention is not limited to that'particular embodiment, and that various changes and modifications may be effected therein without departing from the scope or spirit of the invention, except as defined in the appended claim.

What is claimed is:

A bed spring comprising a wood frame having upper and lower rectangular portions secured together in parallel, spaced apart relation, a flexible grid of non-extensible elongated members arranged in rows extending longitudinally and laterally within said upper frame portion over substantially the entire area of the latter and being pivotally interconnected at the intersections of said rows, non-extensible means securing said grid, at the opposite sides thereof, to the adjacent sides of said upper frame portion, longitudinally yieldable means connecting the opposite ends of said grid to the adjacent ends of said upper frame portion, compression coil springs underlying and supporting only the longitudinally central portion of said grid and being arranged in laterally extending rows, a rigid support member for said coil springs in each of said laterally extending rows and having the lower ends of the related coil springs secured thereto, means securing the ends of each rigid support member to said sides of said upper frame portion so that said coil springs enhance the resistance to flexing of said central portion of the grid under a load applied thereto while said rigid support member associated with each row of coil springs laterally braces the sides of said upper frame portion against the inwardly directed lateral forces exerted thereagainst by said grid.

References Citedin the file of this patent UNITED STATES PATENTS Crutcher Apr. 14, Reddel Nov. 5, Palmer Apr. 19, Feig Nov. 14, Phelps July 8, Richardson May 5, Magyar Oct. 26, Krakauer June 9, Lathrop May 21,

FOREIGN PATENTS France June 11, 

